A file named .ftpquota appeared in the root directory of an addon domain. The file name suggests its purpose. Can anyone tell me more?
It appeared in an AddOn Domain rather than the Primary Domain.

Thanks!

cPanel creates FTP accounts for add-on domains.
The idea is that you might want to give someone else an account for just the add-on domain (e.g. if you're hosting a domain for someone).

Your main domain uses your cPanel account name as the FTP details and so it doesn't have an FTP quota.

Additional accounts can have quotas, hence the file.

If you want to remove the account or change its quota, just go to the "FTP accounts" section of cPanel.

After the FTP Account has been deleted from cPanel relating to the AddOn Domain, delete the .ftpquota file from the AddOn Domain root if it has not been done already.

Thanks Templar.

I do normally delete files that can be a risk to the website.

I also deleted the FTP account for the addon domain as it was not required.

Good to get the explanation!